Reland of Paint collapsed borders of a table as one display item

third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp

Index: third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp b/third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp
index ecaa5b611dff33ec6307bc053d22d93670b876e3..f37ca39f162bc3e82e93f259506cb76115f289c4 100644
--- a/third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp
+++ b/third_party/WebKit/Source/platform/graphics/paint/DisplayItem.cpp
@@ -68,23 +68,6 @@
     return "Unknown"
 
 static WTF::String specialDrawingTypeAsDebugString(DisplayItem::Type type) {
-  if (type >= DisplayItem::kTableCollapsedBorderUnalignedBase) {
-    if (type <= DisplayItem::kTableCollapsedBorderBase)
-      return "TableCollapsedBorderAlignment";
-    if (type <= DisplayItem::kTableCollapsedBorderLast) {
-      StringBuilder sb;
-      sb.append("TableCollapsedBorder");
-      if (type & DisplayItem::TableCollapsedBorderTop)
-        sb.append("Top");
-      if (type & DisplayItem::TableCollapsedBorderRight)
-        sb.append("Right");
-      if (type & DisplayItem::TableCollapsedBorderBottom)
-        sb.append("Bottom");
-      if (type & DisplayItem::TableCollapsedBorderLeft)
-        sb.append("Left");
-      return sb.toString();
-    }
-  }
   switch (type) {
     DEBUG_STRING_CASE(BoxDecorationBackground);
     DEBUG_STRING_CASE(Caret);
@@ -126,6 +109,7 @@
     DEBUG_STRING_CASE(TableCellBackgroundFromColumn);
     DEBUG_STRING_CASE(TableCellBackgroundFromSection);
     DEBUG_STRING_CASE(TableCellBackgroundFromRow);
+    DEBUG_STRING_CASE(TableCollapsedBorders);
     DEBUG_STRING_CASE(TableSectionBoxShadowInset);
     DEBUG_STRING_CASE(TableSectionBoxShadowNormal);
     DEBUG_STRING_CASE(TableRowBoxShadowInset);